On Tichý’s Attempt to Explicate Sense in Terms of Turing Machines

In Tichý (1969), it is shown that semantics of natural language can be pursued procedurally. Tichý supported his argument by defining elementary functions of logic (truth functions, quantifiers) using Turing machines and attempting to define the sense of empirical expressions using a simple semantic version of oracle. From the way how Turing machines and later constructions are defined it follows that even the sense of empirical expressions can be successfully handled but that the sense and denotation can be in principle effectively obtained while the actual value at the actual world can be, of course, never computed. The present paper comments on this attempt and compares the Turing machines argument with the possibilities given by TIL constructions. Turing machines guarantee the effective character of computing while the constructions do not, but expressive power of constructions is incomparably stronger, not only because Tichý’s possible worlds from 1969 are atemporal: they define essentially 1 st order operations and can be reinterpreted as one possible world enjoying (discrete) temporal changes. Both the TM conception and the “constructivist” one know that the question “which possible world is the actual one” cannot be ever answered by effective (computational) methods and their analyses of empirical expressions are therefore compatible.